Cyclocross racing pits riders on bikes with drop bars and knobby tires against each other on multi-lap courses over a mix of grass, dirt, pavement, sand, mud and sections that force riders to carry their bikes over barriers and up stairs and hills. Racers attack from the line, and the intensity doesn’t diminish for the duration of the 30- to 60-minute events -- it’s a redline-all-the-time, full-contact affair. With participation doubling over the past five years, it's also the fastest growing segment of competitive cycling in America. Some attribute this growth to the more laid-back, beer-primed environment at cyclocross races, but cool bikes certainly don't hurt. We've got three rigs that make the grade from the starter's gun well past the finish line.

The dictionary defines a bicycle as “a vehicle with two wheels in tandem, usually propelled by pedals connected to the rear wheel by a chain, and having handlebars for steering and a saddle like seat.” That certainly covers the gist of the invention, but after centuries of design evolution, the world of bikes has grown...